Disposable package for liquid material and method of making same

Abstract

A disposable blister-type package for containing a small quantity of liquid material such as nail enamel including a volatile solvent, constituted of a thermoformed tray defining a liquid-holding cavity with a surrounding rim and a lid covering the cavity and secured to the rim, wherein at least the facing surface portions of the tray and lid are formed of acrylonitrile methylacrylate copolymer. The facing methylacrylate surfaces of the lid and tray are directly bonded together around the cavity to form a leakproof seal that is readily peelable. The seal region of the lid surface is embossed, during the sealing operation, with a pattern of serrations to facilitate peeling. A disposable applicator for the liquid may be enclosed, and similarly sealed, within a second tray cavity also covered by the lid and isolated by the seal from the liquid-holding cavity.

I claim: 
     
       1. A package containing a body of liquid material including a volatile solvent, comprising (a) a molded sheet plastic tray defining at least one cavity, for receiving a body of liquid material, and having a substantially planar rim completely surrounding said one cavity; and   (b) a lid of sheet material extending entirely over said one cavity and secured to said rim to enclose a body of liquid material received in said one cavity; wherein the improvement comprises:     (c) a body of liquid material including a volatile solvent, received in said one cavity;   (d) at least facing surface portions of said tray and said lid, including the tray surface portion facing the interior of said one cavity and extending over said rim, being constituted of a polymeric material resistant to attack by said solvent, said polymeric material being acrylonitrile methacrylate; and   (e) the lid and tray being secured as aforesaid by direct bonding of said polymeric material of said lid surface portion to that of said tray surface portion around said rim for providing a bond that seals the contained liquid material within the cavity and is substantially uniformly releasable when subjected to manual peeling forces to enable removal of the lid from the tray.   
     
     
       2. A package as defined in claim 1, wherein the area of said bond in the surface of at least one of said lid and said tray is embossed with small serrations effective to facilitate release of the bond as aforesaid while still providing an effectively leakproof seal for the contained liquid material prior to such release. 
     
     
       3. A package as defined in claim 2, wherein said tray is formed with a second cavity for holding a disposable applicator for said liquid material, said second cavity being isolated from the first-mentioned cavity by said bond an being itself sealed by an extension of said bond. 
     
     
       4. A package as defined in claim 3, wherein said tray is a thermoformed sheet consisting essentially of acrylonitrile methylacrylate. 
     
     
       5. A package as defined in claim 3, wherein said tray is a thermoformed sheet comprising a polymeric substrate and a barrier layer of acrylonitrile methylacrylate laminated to the lid-facing surface of the polymeric substrate. 
     
     
       6. A package as defined in claim 3, wherein said lid is a sheet comprising a substrate and a barrier film of acrylonitrile methylacrylate laminated to the tray-facing surface of the substrate. 
     
     
       7. A package as defined in claim 6, wherein said substrate comprises successive laminated layers of paper, metal foil and polyester. 
     
     
       8. A package as defined in claim 6, wherein at least one surface of said substrate is imprinted with decorative and/or informative indicia. 
     
     
       9. A method of packaging a quantity of a liquid material including a volatile solvent, comprising (a) molding a plastic sheet having at least a surface portion of polymeric material resistant to said solvent to form a tray including at least one liquid-receiving cavity within a surrounding substantially planar rim, wherein the polymeric material surface portion lines the cavity and the rim, said polymeric material being acrylonitrile methacrylate;   (b) filling the cavity with a predetermined quantity of said liquid material;   (c) covering the cavity and surrounding rim with a lid of sheet material having at least a surface portion, facing the tray and engaging the rim, of said polymeric material; and   (d) bonding the polymeric material of the tray rim to the polymeric material of the lid to provide a bond that seals the liquid within the cavity and is readily and substantially uniformly releasable by manual peeling forces.   
     
     
       10. A method according to claim 9, wherein the bonding step includes embossing the bonded area of at least one of the tray and lid with a pattern of small serrations. 
     
     
       11. A method according to claim 9, wherein the bonding step comprises pressing the lid and tray together around the rim, with application of heat thereto, to provide a bond as aforesaid.